For the uninitiated, Webster’s Dictionary defines a fopdoodle as “a stupid or insignificantfellow; a fool; a simpleton”.

“Slummocking” means to “behave in a lazy, indolent, or clumsy way”.

While Boris’ insult achieved its aim of having people say “Jeremy Corbyn” and “mugwump” in the same sentence as much as possible, immediate reaction to Watson’s jibe was that the election was degenerating into what one tweeter called “regency bantz”.